WASHINGTON (AP) – Average long-term U.S. mortgage rates fell this week for a third straight week as global stock markets continued to be pounded by falling oil prices and worries over economic growth.

Mortgage buyer Freddie Mac says the average rate on a 30-year fixed-rate mortgage declined to 3.81 percent from 3.92 percent a week earlier. That rate has increased from its 3.63 percent average a year ago but remains well below its historic average of 6 percent.

The average rate on 15-year fixed-rate mortgages dipped to 3.10 percent from 3.19 percent.

The continuing tumult in stock markets around the world has pushed up prices of U.S. government bonds as investors seek safety. That has depressed the yields on the bonds, which mortgage rates track.